“双碳”背景下我国稻田生态系统土壤固碳潜力分析  

Carbon Sequestration Potential of Paddy Soil in China under the Carbon Peaking and Carbon Neutrality Goals

作　　者：白龙龙 盛雅琪 徐丽丽[1,2] 高翔 张涌新[3] 邓劲松[1,2] Bai Longlong;Sheng Yaqi;Xu Lili;Gao Xiang;Zhang Yongxin;Deng Jinsong(College of Environmental&Resource Sciences,Zhejiang University,Hangzhou 310058,China;Zhejiang Ecological Civilization Academy,Huzhou 313300,Zhejiang,China;Institute of Carbon Neutrality,Zhejiang University,Hangzhou 310027,China)

机构地区：[1]浙江大学环境与资源学院,杭州310058 [2]浙江生态文明研究院,浙江湖州313300 [3]浙江大学碳中和研究院,杭州310027

出　　处：《中国工程科学》2024年第6期246-256,共11页Strategic Study of CAE

基　　金：中国工程院咨询项目“农田生态系统温室气体减排路径及对策”(2023-XY-23);国家自然科学基金项目(22376179);科技基础资源调查专项(2023FY100102)。

摘　　要：稻田生态系统作为人为耕作条件下形成的土壤生态系统,具有较高的固碳能力和潜力,对我国农业领域实现“双碳”目标具有重要意义。本文基于遥感技术提取2021年的我国水稻种植区信息,构建了5995个图斑模拟单元,应用反硝化-分解(DNDC)模型模拟了2021—2040年全国稻田表层土壤有机碳(SOC)密度的空间分布情况,预测了我国未来稻田SOC的变化趋势。结果表明,在现有种植条件下全国稻田土壤呈现碳汇状态,2021年的稻田表层土壤(0~20 cm)碳储量平均值为4.1 Pg C, 2030年、2040年的对应值分别为4.32 Pg C、4.49 Pg C,稻田土壤碳储量表现为逐年上升趋势;2021—2030年的稻田土壤的固碳潜力为22 Tg C/a,2030—2040年为17 Tg C/a,年均变化率趋缓,稻田土壤固碳潜力逐渐达到饱和状态。未来20年,我国绝大部分地区的稻田SOC密度将出现变化,增加面积明显高于下降面积,最高增长率为9.2%,最大下降率为8%。情景模拟表明,秸秆还田、化肥施用可显著提高稻田土壤的碳储量。相关结论在充分利用稻田土壤的碳汇功能、降低温室气体排放、推进农业领域“双碳”目标等方面具有科学意义和应用价值。The paddy ecosystem,as a unique soil ecosystem formed by artificial cultivation,holds great potentials for carbon sequestration,which is crucial for realizing the carbon peaking and carbon neutrality(“dual carbon”)goals in the agricultural sector of China.This study constructs 5995 simulation units using the rice planting area information acquired through remote sensing in China in 2021.Subsequently,it uses a denitrification-decomposition(DNDC)model to simulate the spatial distribution of surface soil organic carbon(SOC)density in fields in China from 2021 to 2040,and predicts the future trend of the SOC.Results of the study indicate that the paddy soil in China exhibits a carbon sink under the current planting conditions.The average carbon storage of the surface paddy soil(0~20 cm)in China was 4.10 Pg C in 2021 and will be 4.32 Pg C in 2030 and 4.49 Pg C in 2040;the carbon storage will increase year by year.The carbon sequestration potential of paddy soil in China will be 22 Tg C‧a-1 during 2021—2030 and 17 Tg C‧a-1 during 2030—2040;the average annual growth rate will slow down,and the carbon sequestration potential of soil will gradually reach saturation.In the next two decades,the SOC density of paddy fields in most regions of China will change,and the increased areas will be significantly greater than the decreased areas,with a maximum growth rate of 9.2%and a maximum decrease rate of 8.0%.Scenario simulations indicate that straw returning and fertilizer application could significantly increase the carbon storage in paddy soils.These findings hold scientific significance and practical values in fully utilizing the carbon sink function of paddy soils,reducing greenhouse gas emissions,and advancing the“dual carbon”goals in the agricultural sector.

关 键 词：稻田生态系统 土壤碳储量 固碳潜力 DNDC模型 情景模拟 

分 类 号：S153.6[农业科学—土壤学]